Piston and piston bllto



Nav.. Z i926. v

L. H. CORMBER PISTON AND PISTON RING Filed Jan. 5. 1926 Patented Nov, i926,

LEO HENRY CORMIER, 0F DETRQE, MXGHIGAN.

PXSTON AND Application tiled Jennery The present invention relates to piston andring construction for internal combustion engines, and other types of motors or .machines utilizing pistons and rings.

An object of the present invention is to provide `a piston and ring construction wherein the, ring is so constructed and mounted that the three major results sought to be attained in the art may loe aecomplished, such results being the complete :dit ing` of the pistonring groove; conformation of the ring to the shape ot the cylinder Wall; and veontrollalole uniform radial pressure of the ring against the cylinder Wall.

The invention ainis to provide a piston ringstructure wherein the ring is compressible not only axially of the piston but also radially therefrom to provide an effective seal ol' the ring in the groove and also lietween the ring and the cylinder Wall, the pressure being regulated or controlled hy the utilization ot springineinher et de-s sired tension.

Another "feature oit the invention is to provide a piston and ring; construction which ellects the radial and axial compression oil the rin by means which is not readilyr susceptib e to change in its inherent elasticity or resiliency when subjected to intense heat and which Will more readily maintain its original shape and pressure eiffort than devices oi a kindred nature heretofore invented and tested out.

A further objectol' the invention is to provide piston sind ring structure which comprises hut ew 'ports most ot `Which are interchangeable and which may he easily and quickly assembled and separated, and the nieniliers ot the ring structure readily adapting themselves to any inequalities which may exist in the cylinder vvall.

'l`l above, and various other objects end advantages of this invention will in part he described, and in part lie understood troni, the following detailed description et the present preferred embodiment, the same being illustrated inthe accompanying dravvn ingr, wherein:

Fig. l is a lonrfitudinal eentral'seetion taken through a pi n and ring constructed according to the present invention und disposed in a cylinder, the letter heing tregrnentarily illustratedl i Fig, F2 is a transverse section through the1 saine on the line ;/3- 2 ol illip;o 'l

F1552 B is a i'ragl....entary ezels. seetion RESTON TREN@ 5, 1926. Serial No. '79,490.

taken throuirh one side ot the piston and ring mounted in the cylinder,

Fig. 4 is a :fragmentary transverse sec- -tion taken through the structure of Fig. 3 on the line 4f--fl thereof.

Fig. 5 is a perspective view ot the piston ring showing the sections vand parts thereoitl in separated position, and

Fig. 6 is a detail perspective view of the spring ineinber employed.

Referring to the drawing l0 designates a cylinder in which the piston and ring ot this invention may he mounted.

The body 11 of the piston may loe oi any approved type provided With inwardly extending bosses or hearings@ for supportino a `wrist pin 13 to which a connecting ro may he attached in the usual mannera The upper part of the piston body il is provided 'with a central upwardly tapering post lli provided exteriorly with an annular seat l5 which preferably slopes outwardly and downwardly to a slight degree.. The upper end oit the post 'terminates in en eX- ternally threaded stud lli which closes the upper end of the post lll and which aittords a support lor a lock nut l? provided in its upper side with depressions or openings for the reception oit a spanner Wrench or like tool which muy Joe used :tor turning the lock nut 17.

'lhe piston 1l 'has a removable head 18 provided with e central downwardly flaring opening adapted lto snugly receive the post 14 upwardly theretl'irougli, and 'which is provided centrally and in its upper face with a recess or counterbore for the recepn tion of the lock nut i7. The piston head 18 is provided in thecounterhore With an upivadly 'daring annular Wall 'i9 and the lock nut li" has a correspondingly inclined peripheral Wall 20 adapted to seat against the head i8 and loind the saine downwardly on the post ist and toward theseat 15. To

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reduce the Weight ol" the head i8, the latter groove 22 with an inclined or cam shoulder 24 extending annularly about the head and facing downwardly and outwardly with respect thereto.

The improved piston ring is adapted to,

side of the ring member terminate in spaced apart inclined or bevelled end walls 29 which are substantially parallel to each other. The upper ring member comprises a pair of semi-circular sections 30 and 31 which are of less width than the lower ring member and are adapted to seat against the upper portion of the .shoulder 24. 'llhese sections 30 and 3l of the upper ring member have their adjacent end portions at opposits sides of the member spaced apart and terminating respectively in parallelstraight end walls 32 and inclined or bevelled end walls 33.

lln order that the ring may conform to the curvature of the wall of the cylinder 10 and remain always in a predetermined deinite relation thereto, means isprovided for holding the ring members from turning one upon the other and from turning with respect to the piston. |lhis means comprises a pair ot locking pins 34 which are partially seated in correspondingly shaped openings formed in the inclined shoulder 24 near its upper end, or at least at a point above the lower ring member. 'lhese pins 34 project downwardly and outwardly at substantially right angies to the shoulder 24 and engage between the straight walls 32 ot the upper ring niember and into a socket 35 which is formed in the lower ring member at the inclination of the pin so as not only to anchor the lower ring member against turning, but to also support the pin against displacement from its opening in the piston head. Fig. l shows two pins 34 but the number et pins may be reduced or increased as, jtounfd desirable.

ln order to fill in the space at the lower end ot the piston head 13 which provides a ring groove, a follower ring 36 is employed and is slidably fitted about reduced end ot the piston head 18 and against the lower side of the lower ring member and is given suitable axial length and thickness to project below the head 13 te stand out therefrom in proximity to peripheral. portions et the ring.

ller the purpose ot creating a uniform radial pressure upon the piston ring, a spring disk 37 is provided which is of concavo-con- 'vex form having a central opening38 of suitable size to tit over the post 14'01": the piston 11 and which, at its inner marginal portion, is adapted to seat upon the shoulder 15 at the base of the post. The piston head 18 is held by the lock y nut 17 downwardly against the inner marginal portion of the spring disk 37 to bind it in place about the post and on the seat 15. rlhe spring disk 37 is of sucient diameter toengage at its outer marginal edge portion beneath the follower ring 36, and is provided with a plurality of ,radial slots 39 permitting the free expansion or upward springing of the disk against the lower edge of the follower ring 36 to urge the same upwardly against the piston ring.

The disk 37 lies closely to the top of the piston body 1l so as to leave but a small opening beneath the spring disk. The upper pressure of the spring disk 37 against the follower ring causes the latter to compress the piston ring sections or members together and to causethem to slide upwardly on the shoulder 244, expanding the piston ring members and variably binding them against the inner wall of the' cylinder 10. The upper ring member is provided with an inclined inner edge 40 `which corresponds to the inclination of the shoulder 24 and seats thereagainst. rl`he locking pins 34 hold thepiston ring from turning, the upper member by Vengaging betweenthe end walls of its sections 30 and 31 and the lower portion by engaging in the sockets 35. llt is apparent that the spring pressure may be controlled by binding the piston head 18 more or less over the post and against the inner edge portion ol the spring disk 37. The sections 25 and 26, and 30 and 31 of the lower and upper piston ring members are thus forced outwardly and together for closely fitting the cylinder wall and for eectively closing the ring groove or space. ln order to facilitate the tightening or removal of the lock nut 17, a plurality oit annular openings 41 are provided therein and in which may be inserted a pinwrench or the lilre.

lt is of ceurse understood that various changes and modifications may 'be made in the details ot' construction and design ot the above specilically described embodiment oil the invention without departing vliroi'n the spirit thereof, and restricted only bv the scope of the following claims.

lfifhat is claimed is:

ln combination with a pistn having an upstanding central portion, an adinstable ring fitting over said central portion, s ring groove in said adiustable ring with a downwardly and outwardly racing shoulder, an expansible piston ring fitting against said shoulder, and spring means edjustably mounted between the adjustable the aving an outwardly inclined shoulder fac` ing the other part, an expansible pistn ring fitting in the groove against. said shoulder to slide thereon, a follower ring positioned against the piston ring at the side of the latter remote from the shoulder, and a spring member interposed between the parts ofthe piston and engaging said follower ring to urge thesame against the piston ring and expand it against said inclined shoulder.

3. In combination with a piston having a fixed body and an adjustable head mounted against said shou thereon, saidV head being provided with a ring groove having an upper shoulder facing downwardly and-outwardly, superposed expansible ,ring members provided with inclined inner edges seating on said shoulder,`

and a spring member mounted between said adjustable head and fixed body of the piston to variably compress said ring members together and slide the same upwardly over said shoulder to expand the ring members.

4. In combination with a piston body having a post projecting upwardly from its central portion, ,and a head detachably fitting over the-post, said head having a ring groove in its lower part and with an outwardly inclined shoulder at the upper end of the groove, an expansible piston ring seated against said shoulder in the groove, a follower ring in said' groove against the piston ring, and a spring disk fitting over the post and clamped between thelpiston body and head for yielding enga ement 'against the follower ring to force t e piston ring upwardly about the inclined shoulder to expand the piston ring.

5. In combination with a two part piston, one. part having a post on its outer end adapted toreceive the second part thereover andsaid post .having'an annular shoulder at its base, a spring disk of concave-'convex form provided with a central opening fitting over said post and adjustably binding on said shoulder under action of said other member of the piston, said other member of the piston having a reduced lower end with an inclined shoulder facing downwardly and outwardly, an ex ansible piston ring seated lider in the reduced portion of said other piston member, and a f ollower ring interposed between the piston ring and said disk for' expanding the piston ring up-l wardly over said inclined shoulder.

6. In combination-:with a piston having a body part and a head, said body ,part having a central post projecting upwardly therefrom and rovided with a raised seat about the base o the post, said head having a central o ening and fitting over the post, means for binding the head over the post and t0- ward said seat, a dislied spring disk having a central opening and fitting over the post upon said seat and held thereto by said head, said disk having radial slots in its outer portion to permit free flexing of the disk, said head having a ring groove in its lower part and provided with an upwardly inclined shoul er at the top 'of the groove, an expansible piston ring. in said vgroove engaging the shoulder," and a `follower ring in the lower end of the groove betweenthe outer portion of the disk and the piston ring for expanding the latter upwardly over said shoulder.

7. In combination with a piston having a body portion and a head, a spring member interposed between the body portion and the headand extending outwardly betweeny the same, said head having a ring groove above the spring member and an upwardly inclined shoulder at the top of the groove, a pair of ring members each comprising semicircular sections fitting in the -ring groove against said shoulder, follower means between said spring member and said members to urge the latterupwardly on the shoulder to expand the ring members, and a locking pin projecting from said shoulder and engaging between the spaced ends of the upper ring member sections,"a section of the lower ring member having a socket therein to receive the lower end of said 4locking pin whereby the. locking pin may hold both of the ring members against. turning relatively to one another and to the piston head.

8. In combination with a piston body having an upstanding central portion, a ring like head fitting about wall inclined downwardly and inwardly from its circumferential face, an expansible piston ring in lsaid groove fitting against said face, and spring means mounted between said piston body and ring like head for-compressing the piston ring against said inclined ace to close the groove and expand the piston ring against a cylinder wall.v

' LEO HENRY CORMIER..

ring j said central portion, said head provided with a ring groove having a- 

